Wednesday, March 08, 2006

Split Operations - When and How?

As the spots increase, so do the number of stations who call us. The goal of the DX operator working the 'pileup' is to work as many stations as possible, as smoothly and as quickly as possible. You are the DX station - you called CQ - you made the mess - it's up to you to control it. No one is going to control it for you, and an out of control pileup is one of the biggest causes of frustration on the HF bands for lots of hams. One of the big problems with pileups is that many of the stations calling can't hear the DX because of the QRM caused by other stations calling also. The simplest and most efficient system for solving this problem is the 'split' operation - where the DX station transmits on one frequency and listens on a different frequency, or over a range of different frequencies.

When do you need to go to a split operation ? When the people you are giving reports to are not answering, or when you are not getting your report from the station you are working because of other stations who are continuously calling. Simply, when the QRM starts slowing you down. Split operation moves the QRM and you are no longer forced to wait for 20 or 30 stations to stop calling you so you can work one of them Modern transceivers today come equipped with two VFO's - some even come with two receivers. The RIT (on Yaesu rigs, the CLARIFIER) can also be used for split operations. The primary goal of a split operation is to get the calling stations (the pileup) far enough away from the DX station so that the pileup causes no interference on frequency the DX station is transmitting on.

For CW operations, 2 KC's is usually a good starting point. On CW, you can announce that you are listening up, i.e., QRZ 4Z5MU UP which is usually all that is need to make the pileup move away from your transmit frequency. If the pileup doesn't respond immediately and other stations continue to call on your frequency, UP 2 UP 2 UP 2 UP 2 DE 4Z5MU will usually do the trick. Simply turn the RIT on and tune up the band and listen for stations calling you, or, if you prefer, use the other VFO on your rig to receive. Tune up and down over a range of 2 or 3 KC's - fortunately there are a few DX'ers left who are smart enough to not just tune up 2 KC's and send their call a dozen times. It's hard to copy anybody even with a 250 cycle filter when 75 stations zero beat the same frequency and call you, so move your receive frequency around. By moving, you will increase your rate by working the good operators who know what TAILGATE means, and the ones who quickly figure out the direction you are tuning.

On SSB, the process of working a split operation is basically the same but since you need to move the pileup farther away from your transmit frequency (to disable the affect of Mr. Splatter), using two VFO's is a must. Again, most modern rigs with two VFO's have the A=B button. Press it, which sets the second VFO to the frequency and side band you are currently operating on. Tell everybody to standby, and then activate the second VFO as the receive VFO. Tune up (or down) the band at least 5 to 10 KC's, find a quiet frequency, then announce to the pileup where you will be listening. For example, if you are operating on 14.195, move the pileup up to 14.210. It's fine to move them down, but the usual procedure is to move them up. Again, as on CW, it's difficult to pick out callsigns when too many stations are calling you on the same frequency - so simply spread them out. Listen from 14.260 to 14265, or to 14.270.

Do's and Don'ts of split operation. It's very important to tell people where you are listening. As new stations arrive to join the pileup, they need to be instructed quickly as to what's going on. On CW, always include the UP after your callsign (and please don't forget to send your callsign after EVERY station you work - don't expect the new guys who just showed up to know from your fist who you are).On SSB, simply give your listening frequency after every contact - 4Z5MU 210 - or - 4Z5MU 210 to 220. It's also important to check your transmit frequency on occasion - no matter how specific you are you will always get the guy who can't figure out what's going on and who zero beats you and calls you for an hour. You want to make sure your transmit frequency is CLEAR, that's why you are working split. If you listen on your frequency and find 3 stations calling, DO NOT work them - MOVE THEM. If you WORK them, then you'll move the pileup down to your frequency and you'll have to start over. Move them by simply announcing where you are listening - even if you have to announce it ten times - do it until they all move off and your transmit frequency is clear again. It's imperative that you keep your transmit frequency clear - if you don't, the guys who are calling you there will be joined by the RADIO POLICE. The RADIO POLICE are the guys who already worked you, or have nothing better to do but listen to you, and they will begin telling the lost souls you are listening up - next thing you know the lost souls and the RADIO POLICE have you covered in QRM. Before you begin any split operation, make sure the frequency you are going to listen on is CLEAR and not being used by other hams. If you tell people to call you 10 KC's up, remember they won't be listening where they are transmitting - they are listening to you - so don't plop your pileup down right on top of somebody else who is having a QSO. Don't get carried away with how wide of a frequency range you need to listen on - 10 or 20 KC's is usually enough to accommodate half the world.

One of the worst demonstrations of poor operating was a Clipperton DXpedition back in the late 70's. The whole world wanted to work them, and they would show up on 14.195 and start listening from 14.200 to 14.300 - which would clobber who knows how many QSO's that were already in progress up and down the band. Start listening on one frequency. If things get difficult, spread them out to 5 KC's, or worst case 10 KC's, but don't clog up half the band with your pileup. Do pay attention to your QSO rate - if you are just passing out signals reports, on CW you should be working 2 or 3 stations a minute. On SSB 3 or 4 a minute. If things slow down, it's usually because your transmit frequency is getting QRM - go clear it off.

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"You see, wire telegraph is a kind of a very, very long cat.You pull his tail in New York and his head is meowing in Los Angeles.Do you understand this? And radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat.
--Albert Einstein